Method for providing a dental prosthesis and a positioning guide for placing the dental prosthesis

ABSTRACT

A method for designing a dental prosthesis and a positioning guide for placing the dental prosthesis on implants in the jaw while maintaining proper occlusion relates to designing the dental prosthesis and the positioning guide prior to implant placement.

TECHNICAL FIELD

Disclosed herein is method for designing a dental prosthesis and apositioning guide for placing the dental prosthesis on implants in thejaw while maintain proper occlusion. In particular the method relates toa method for designing the dental prosthesis and the positioning guideprior to implant placement. Accordingly, the disclosure relates to amethod and a kit of components suited for one-day implant surgerythereby reducing the time the patient spend in the dentist chair.

BACKGROUND

So-called one-day implant surgery are becoming popular and common withdental implantologists and even for more general dental practitioners.

The advantage of getting everything done in one day is of course timesaving, especially for the patient who do not have to go back forseveral appointments spread over several days. Even further, where ithas been common to let the implants heal and settle for a period afterplacement more practitioners are starting to apply an immediate loadpractice. This is based on the experience that if you load the implantsimmediately after placement the risk of implant rejection and boneregression seems to be reduced.

Accordingly, there is an interest in even further facilitate suchone-day implant surgeries.

As disclosed herein it will for example be understood that there is aneed for a prosthesis, temporary or permanent, that can be placed on theimplants immediately after surgery. This requires that the prosthesis iscreated before surgery and therefore needs to take into account possibledeviations in implant placement that may occur during implant placement,e.g. when drilling the bore.

Even further there is also a desire to ensure that the proper occlusionbetween the prosthesis in one jaw and the teeth in other jaw (natural orartificial) is maintained. Lack of proper occlusion often leads todiscomfort or even pain for the patient. This is also addressed by thefollowing disclosure.

SUMMARY

In one aspect herein there is disclosed a method of creating a digitalprosthesis design of a prosthesis, which when manufactured can be placedon at least one implant placed in a first jaw of a patient and creatinga digital guide design of a positioning guide, which when manufacturedcan be used to position the prosthesis on the at least one implant sothat the manufactured prosthesis is in a desired occlusal contact with adental anatomy of a second jaw opposite the first jaw, wherein themethod comprising steps of,

-   -   obtaining a digital first jaw model comprising a surface        representation of at least a part of the first jaw and of an at        least one expected implant site comprising a digital abutment        representation of an abutment arranged at the at least one        expected implant site,    -   creating the digital prosthesis design comprising a distal        prosthesis surface and a proximal prosthesis surface wherein the        proximal prosthesis surface comprises at least one abutment        hole, and creating the shape of the abutment hole larger than        the digital abutment representation,    -   obtaining a digital second jaw model of the second jaw        comprising a surface representation of at least a part of the        second jaw opposing the at least one expected implant site, and    -   creating a digital guide design of the positioning guide        comprising a distal guide surface which at least partly        comprises a shape corresponding to the shape of a part of the        digital second jaw model and a proximal guide surface which at        least partly comprises a shape corresponding to the shape of a        part of the distal prosthesis surface.

One effect of providing abutments holes in the digital prosthesis designthat is larger than the digital abutment representation is that themanufactured prosthesis can be placed even if the at least one implantshas moved a little from its respective expected implant site.

Creating the shape of the abutment hole larger than the digital abutmentrepresentation can for example be done by creating the shape of theabutment hole at least partly on an enlarged shape of the digitalabutment representation. In another embodiment creating the shape of theabutment hole can for example be done based fully or partly on a simplegeometrical shape which is larger than the digital abutmentrepresentation. Such geometrical shape can for example be hexagonal,rectangular or cylindrical, or another volume which will cover theabutment when the prosthesis is manufactured.

Accordingly, this solves the problem of facilitating placement of theprosthesis.

However, by providing such enlarged abutment holes there is also anincreased risk that the manufactured prosthesis may be placed so that abad bite occurs. In other words, the jaws will end in incorrectocclusion when biting together.

Accordingly, the effect of providing using a positioning guidemanufactured based on the digital guide design as disclosed ensureproper positioning of the prosthesis on the at least one implant andthus solves the problem of providing proper occlusion.

Although discussed later in the disclosure it is difficult to strictlyquantify the size and shape of the abutment hole, e.g. by the enlargedshape of the digital abutment representation, e.g. that it should have aspecific numerical offset. In general it will be the experience of thepractitioner or designer that determine the specific enlarged shape,which will for example be affected by the number of implants andabutment, the abutment types, material type etc. Accordingly the meaningof the step of creating the shape of the abutment hole at least partlyon an enlarged shape of the digital abutment representation, should beunderstood in relation to the need of providing a positioning guide inorder to maintain the proper occlusion of the prosthesis duringplacement on the at least one implant. Thus, if the abutment hole issized so that the prosthesis can be placed without the need of apositioning guide to maintain the proper occlusion between theprosthesis and the opposing dental situation (e.g. antagonist teeth)then the digital prosthesis design or a prosthesis manufacturedtherefrom does not fall within the disclosure herein. However, if thestep of creating the shape of the abutment hole at least partly on anenlarged shape of the digital abutment representation provides a digitalprosthesis design or a prosthesis manufactured therefrom with anabutment hole which necessitates the need of a positioning guide inorder to place the prosthesis in proper occlusion then the digitalprosthesis design or a prosthesis manufactured therefrom falls withinthe disclosure herein.

The step of creating the shape of the abutment hole at least partly onan enlarged shape of the digital abutment representation should beconstrued broadly as there are many options of doing this in a digitaldesign environment. E.g. a person used to work in CAD softwareenvironment having the appropriate models would easily do this andequivalents thereof when given and described the step of doing so. Forexample, the shape of the abutment hole could initially be shaped to fitthe digital abutment representation and then enlarged, e.g. byoffsetting. The desired effect of this feature is to create a prosthesisbased on the digital prosthesis design which have an abutment hole thatgive some play in moving the prosthesis in a direction transverse to theinsertion direction (direction which the prosthesis is placed onto theimplant and abutment) when the prosthesis is placed on the abutment (andthe prosthesis is not fixed to the occlusion using the positioningguide).

The method disclosed may advantageously be performed in a digital designenvironment such as CAD design software. In particular the method couldbe provided in a dental specific CAD software, such as the 3Shape DentalSystem. Accordingly, the method can be run on software that can beexecuted on a computed device such as a well known desktop computercomprising physical or cloud storage for storing the software, aprocessor for executing the software, a monitor for presenting thedigital design environment to the user and a mouse and a keyboard orsimilar input device in order for the user to interact with the digitaldesign environment presented on the monitor.

In one embodiment the method comprises the step of obtaining a digitalfirst jaw model further comprises the steps of,

-   -   obtaining a surface scan of the expected implant site,    -   obtaining a radiographic image of the expected implant site, and    -   arranging the surface scan and the radiographic image in a        common coordinate system.

This advantageously provides a digital first jaw model that providessurface scan which often is of high resolution and therefore is suitableto use as a basis for designing the prosthesis. Such surface scans canfor example be obtained by scanners well known in the art such as intraoral scanner, for example the TRIOS scanner, which uses optical scanningmeans to obtain a 3D surface scan.

However, the surface scan cannot detect structure below the surface ofthe jaw. Accordingly, if the dentist wants to do implant planning it isan advantage to be able to consider structures such as bone density,teeth roots, nerves etc. However, radiographic images often have a roughresolution since a higher resolution typically requires a higherradiation dose, which is not recommended. A typical radiographic imagethat is used in dentistry is a CBCT (cone beam computed tomography)image that provides a 3D radiographic image.

Thus, by combining the two a digital first jaw model is provided whichis suitable for designing a prosthesis and for implant planning.

Furthermore, in order to properly plan and design the surface scan andradiographic image is arranged in one coordinate system so thatidentical features in the surface scan and radiographic image are placedat the same coordinates.

In some cases the implant may already have been placed and an abutmenthas already been placed in the implant. In such cases the digitalabutment representation represents the position of an already placedimplant and abutment. However, it may still be relevant to use themethod disclosed herein since the digital first jaw model may not becompletely accurate or the implant may risk shifting a little before theprosthesis has been manufactured.

In another embodiment the method further comprises that the digitalabutment representation is a digital abutment model.

A digital abutment model is a CAD model which is a digitalrepresentation of an abutment that the user anticipates using in theplaced implant. Abutment are generally known in the art and can beunderstood as an interface element between the implant wherein it isplaced and the prosthesis which is placed on the abutment. Abutmentscomes in many types and some by be of the shelf standard abutmentswhereas others are customized to fit the specific implant in a specificoral situation.

The abutment(s) could for example be one or more of the following typeof abutments, Ti-base abutments, customized abutments, stock abutments,multiunit abutments, temporary abutments/cylinders, abutment locators,healing caps, hybrid abutment, straight/angled abutments,single/two-piece abutments and/or cement/screw-retained abutments.

For example, in embodiments, wherein the method further comprises thestep of selecting the digital abutment model from a digital abutmentmodel library the user is allowed to chose between a number of digitalabutment models for use in the method as disclosed.

This provides the user to try different abutment types on the digitalfirst jaw model and get an understanding of which abutment seems bestsuited for a specific case.

In an even further embodiment the method further comprises the step of,

-   -   providing a digital implant model,    -   arranging the digital implant model at the expected implant        site,    -   arranging the digital abutment model with the digital implant        model.

Accordingly, the user is not only able to test digital abutment models,it is also possible to plan proper implant placement by arranging thedigital implant model at the expected implant site or even testdifferent positions before deciding on one specific.

Moreover the digital abutment model and the digital implant model may bepaired together so that the software automatically places them in aproper relative arrangement, which corresponds to the arrangement thatwill be created when the corresponding respective physical implant andabutment is placed in the first jaw.

In order to keep the manufactured prosthesis and positioning guidetogether during placement a friction fit or a detachable assembly, suchas a weak gluing, can be provided so that when the prosthesis have beenplaced and it have been fixed to the abutment, e.g. by gluing, theprosthesis and positioning guide can be separated.

However, in one embodiment, the step of creating the digital prosthesisdesign further comprises the step of,

-   -   designing a support structure on the digital prosthesis design,        wherein the support structure is designed to contact at least a        part of the surface representation of the first jaw, for example        by extending the support structure proximally from the digital        prosthesis design.

This ensures that when the prosthesis is arranged in the mouth and thepatient bites down the prosthesis will not detach from the positioningguide since the support structure has the effect the prosthesis ispressed into the positioning guide and held in place.

The method disclosed herein is particularly suited for designingdentures. Accordingly, in one embodiment the step of creating thedigital prosthesis design comprises the step of,

-   -   creating a digital gingiva model of the prosthesis, and    -   creating at least one tooth model of the prosthesis extending        distally from the digital gingiva model.

However, the person skilled in the art will understand that other typesof dental prostheses may be designed using the disclosed method.

The enlarged shape of the abutment hole relative to the digital abutmentrepresentation can be provided in different ways.

In one embodiment this can be provided by the method wherein the step ofcreating the shape of the abutment hole comprises the step of,

-   -   offsetting the digital abutment representation outwards.

Advantageously such an offset is more than 0.5 millimetres, for examplebetween 0.5 and 1.5 millimetres. This provides for sufficient space toaccommodate most changes in implant placement, however, a higher offsetmay be desired relative to the number of implants used to fix theprosthesis.

And in an even further embodiment the step of creating the shape of theabutment hole comprises the step of,

-   -   removing undercuts comprising reducing the digital prosthesis        design so that an overlap between the digital prosthesis design        and the digital abutment representation is removed when        relatively shifting the prosthesis design and the surface        representation of at least a part of the first jaw along a        desired insertion direction between a position where the digital        abutment representation is outside the abutment hole and a        position where at least a part of the prosthesis surface and the        surface representation of at least a part of the first jaw align        with each other.

As can be understood removing undercuts ensures that the prosthesis maybe correctly placed from at least one insertion direction.

In another aspect there is disclosed a method of manufacturing aprosthesis and a placement guide for placing the temporary prosthesis ina desired position in the oral cavity comprising the steps of,

-   -   creating a digital prosthesis design of the temporary prosthesis        as disclosed herein,    -   creating a digital guide design of the positioning guide as        disclosed herein,    -   manufacturing the prosthesis based on the digital prosthesis        design using a 3D manufacturing process, and    -   manufacturing the positioning guide based on the digital guide        design using a 3D manufacturing process.

Such 3D manufacturing process can for example be 3D printing and/or 3Dmilling. Both are well known 3D manufacturing processes.

In an even further aspect there is disclosed a kit comprising aprosthesis for placing on at least one implant placed in a first jaw ofa patient and a positioning guide for positioning the prosthesis on theat least one implant so that the prosthesis is in a desired occlusalcontact with a dental anatomy of a second jaw opposite the first jaw.

By providing such a kit the practitioner can easily proceed with placingthe prosthesis.

In such a kit the prosthesis and the positioning guide can bemanufactured as disclosed previously by 3D manufacturing. This enablesthe dentist to obtain the kit the same day as the planning and thusensuring a one-day treatment as discussed.

Even further the kit may comprise a drill guide adapted for guiding adental drill for drilling at least one bore in the first jaw for placingthe at least one implant.

This provides a kit with three parts which facilitates a one-daytreatment.

In yet another aspect the prosthesis manufactured based on the digitalprosthesis design and the positioning guide manufactured based on thedigital guide design is used together with a method and/or a system fornavigated implant surgery. This can for example be the X-Guide™ systemfrom X-NAV Technologies which provides dynamic 3D navigation thatdelivers guidance for providing a bore implant with accurate position,angle and depth for implant placement.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional objects, features and advantages of thepresent invention, will be further described by the followingillustrative and non-limiting detailed description of embodiments of thepresent invention, with reference to the appended drawing(s), wherein:

FIG. 1A-1D shows one embodiment of a method as disclosed herein forcreating a digital prosthesis design and a digital guide design, and

FIGS. 2A and 2B shows another embodiment of a digital prosthesis designand a digital guide design and also shows a digital drill guide designused together with the above.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanyingfigures, which show by way of illustration how the invention may bepracticed.

An embodiment of the method disclosed herein is shown in FIGS. 1A-1D,wherein it is shown how a digital prosthesis design 10 and a digitalguide design 20 is created.

Initially a digital first jaw model 30 is obtained. The digital firstjaw model is a representation of the mandible (lower jaw), however themethod disclosed herein could just as well be applied to an embodimentwhere the digital first model is a representation of the maxilla (upperjaw). In FIG. 1A the digital model is seen from an occlusal view.

In FIG. 1B the digital first jaw model 30 is seen in a cross sectionalong the line A-A in FIG. 1A between longitudinal sections I-I andII-II. As can be seen the digital first jaw model 30 is formed by asurface scan 31 and a CBCT scan 32 of the oral situation. The digitalfirst jaw model may comprise other representations of the oral situationas well. For illustrative purposes the surface scan 31 and the CBCT scan32 of the first jaw are shown slightly offset, however, these willtypically be aligned together so that they are represented in correctposition relative to each other in a common coordinate system.

The surface scan 31 can advantageously be obtained directly by an intraoral scanner, such as the TRIOS scanner sold by 3Shape TRIOS. However,it may also be obtained by scanning a dental impression or a gypsummodel of the first jaw. Surface data can be stored in a so-called STL orsimilar file format which is read into the system and processed in orderto visualize the first jaw. The CBCT scan 32 of the first jaw can beobtained by conventional CBCT (Cone Beam Compute Tomography) scanner onthe market. CBCT data can be stored in a so-called DICOM file formatwhich is read into the system and processed in order to visualize thefirst jaw.

The advantage of using a surface scan 31 in combination with a CBCT scan32 is that a surface scan typically has a higher resolution than a CBCTscan. Thus, a surface scan 31 can be advantageous to use as a base fordesigning prostheses, surgical drill guides and other dental appliance,whereas the CBCT scan provides sub surface information which isimportant when planning for invasive procedures such as implantplacement.

The digital first jaw model 30 thus forms a representation of the jaw ofthe scanned person which in the current embodiment shows among othernumerous dental features such as a single tooth 33, gum surface 34, gumthickness 35, sub-surface tooth structures such as a tooth root 36 ofthe tooth 33, jaw bone 37 and the mandibular nerve 38.

Based on the established digital first jaw model 30 a user can proceedto do implant planning as shown in FIG. 1C. In the current embodimentthe user proceeds with planning for two implants taking intoconsideration one or more dental features such as the mandibular nerve38, density of the jaw bone 37, teeth roots etc. The user is usingdigital implant models 39, 40 which represents implants that heanticipates using during implant placement and places them accordingly.Such digital implant models are preferably CAD models which can be usedin respective CAD software and manipulate with in a digital designenvironment.

The user will also choose suitable abutments, similarly represented bydigital abutment models 41, 42, and arrange them in the correspondingdigital implant models. Similarly as above the digital abutment modelsare preferably CAD models which can be used in respective CAD softwareand manipulate with in a digital design environment.

When the user is satisfied with the implant planning he can then proceedto design the digital prosthesis design 10 and the digital guide designas shown in FIG. 1D. In order to do this, the user will obtain a digitalsecond jaw model 60, which in the current example is the maxilla (upperjaw). However, it could also be a digital model of an opposingprosthesis, such as a designed denture or a scan of an existing denture.Furthermore, the digital second jaw model 60 is in the currentembodiment only a surface scan provided by an intra oral scanningprocess. However, as disclosed above such a surface scan can be providedby other means, such as scanning an impression or a gypsum model.

Similar to what was discussed in relation to the digital first jaw modelthe digital second jaw model could also be a representation of themandible when the digital first jaw model is a representation of themaxilla.

The user can then proceed to create the digital prosthesis design 10based on the digital first jaw model 30 and the digital second jaw model60. The digital prosthesis design 10 is in the current example processedas a solid CAD model. This means the in the digital design environmentthe digital prosthesis design 10 is handled as an object with athickness and a watertight mesh defining the full shape of the CADmodel. The digital prosthesis design is formed by a distal prosthesissurface 80, which is the surface facing the digital second jaw model 60,and a proximal prosthesis surface 11, which is the surface facing thedigital first jaw model 30. In other words, the distal prosthesissurface 80 can in general be considered to be defined by the virtualteeth and virtual gingiva anatomy surface, which includes the occlusalsurface that will be in contact with the surface of the digital secondjaw model 60 when evaluating occlusion, for example by using a virtualarticulator. The proximal prosthesis surface 11 can generally beconsidered the surface of the manufactured prosthesis which when placedon the implants face the gingiva of the first jaw.

The proximal prosthesis surface 11 is designed primarily based on thesurface scan 31 and the planned placement of the implants represented bythe digital implant models 39, 40 and the abutments represented by thedigital implant models 41, 42 and can comprise the following steps:

-   -   a) Generate a digital intermediate proximal surface (not shown)        of the digital prosthesis design 10 by duplicating a defined        part the surface scan 31,    -   b) Subtract the implant models and the abutment models from the        CAD model of the digital prosthesis design 10 using a Boolean        subtraction. Since the model of the temporary prosthesis 10 is        considered a solid CAD model, intermediate abutment holes can be        provided by performing a Boolean subtraction,    -   c) Generate the abutment holes 90,91 by offsetting the        intermediate abutment holes to provide a gap 81, 82 between the        abutment holes and the models of the implants and the abutment,        and    -   d) Remove undercuts by modifying the digital prosthesis design        so that it can freely be moved relative to the digital first jaw        model and the abutment models along at least one linear movement        (insertion direction) between a position where the abutment        models can be received in the abutment holes and a position        where they are outside the abutment holes without the digital        prosthesis design and the digital first jaw model overlapping or        otherwise conflicts.

By expanding the abutment holes 90, 91 as described above, in particularin step c) and d) tolerances can be taken into consideration whenplanning for the implant placement. Such tolerances can for example besurgical tolerances such as the drill not engaging the jaw bone in theexact position desired or scanner tolerances where the accuracy neededexceeds the accuracy of the digital first jaw model.

In addition the user is planning to extract the tooth 33. In order tomake room for healing and avoid pressure in that area a recess 83 isdesigned in the proximal prosthesis surface 11 opposite the plannedextraction site 84 of the digital first jaw model 30.

The distal prosthesis surface 80 can be generated by designing ananatomy of the prosthesis as described in the art so that the occlusivesurface thereof ensure proper occlusion against antagonist teeth of thedigital second jaw model 60.

With the digital prosthesis design 10 properly created the digital guidedesign 20 can subsequently be generated.

The digital guide design 20 is formed with a proximal guide surface 21which at least in part comprises the complementary shape of the distalprosthesis surface 80. This can for example be provide by a Booleansubtraction of the digital prosthesis design 10 from the digital guidedesign 20.

Similarly, the digital guide design is formed with a distal guidesurface 22 that is generated by a Boolean subtraction of the digitalsecond jaw model 60 from the digital guide design 20.

Accordingly, seeing that the abutment holes 90, 91 are oversized thereis a risk that a prosthesis manufactured based on the digital prosthesisdesign is placed incorrectly if not guided properly. Accordingly, byusing a positioning guide manufactured based on the digital guide designthe position of the prosthesis is ensured even if the implants was notplaced exactly as planned, thereby ensuring the desired occlusionbetween the prosthesis and the opposing jaw.

FIG. 2A shows a digital kit 200 comprising a digital prosthesis design201 in the form of a digital denture comprising a digital gingiva model202 having digital teeth models 203 provided on the distal surface ofthe digital gingiva model and a digital guide design 204. The digitalkit 200 may be manufactured using conventional 3D manufacturingtechniques. Accordingly the kit can be provided to a user in digitalform whereby they can produce the kit part themselves or the kit can beshipped in physical form ready to be used by the practitioner.

A digital guide design 204 is arranged on the digital teeth model.Although not shown the proximal surface 205 of the digital guide modelcomprises proximal recesses for receiving at least a part of the digitalteeth models 203.

The distal surface 206 of the digital guide design comprises distalrecesses 207. The distal recesses 207 are designed based on the opposingdental situation (not shown). In the current embodiment the opposingdental situation is formed of antagonist teeth (not shown). The scan ofthe opposing dental situation is then used to generate the distalrecesses 207. This can for example be done by a Boolean subtractionwhich a person skilled in the art would be able to perform.Alternatively, these recesses could also be provided based on thedigital artificial teeth of an opposing denture.

Although not shown the proximal surface 208 of digital prosthesis design201 is formed with two abutment holes (not shown) slightly oversized inorder to accommodate for possible implant movement that could haveoccurred during implant placement so that the prosthesis manufacturedbased on the digital prosthesis design 201 can be properly placed on theabutments (not shown.

In addition, the digital kit 200 can also include a digital drill guidedesign 220 as shown in FIG. 2B. The digital drill guide design 220comprises four drill guide bores 221,222,223,224. When manufactured thedrill guide bores are used to guide a drill into the jaw bone in orderto create implant bores in the jawbone wherein the implants (not shown)for supporting the prosthesis (manufactured based on the digitalprosthesis design 201) when arranged on the jaw of patient.

The digital drill guide design 220 is also formed with anchor bores225,226,227 which is used for establishing bone anchors, which arescrews that secures the drill guide to jaw bone during implant boredrilling.

The proximal surface 228 of the digital drill guide design 220 isdesigned based on a scan of the gum surface of an edentulous patient inwhich the prosthesis manufactured from the digital prosthesis design 201is to be placed.

The invention claimed is:
 1. A method of creating a digital prosthesisdesign of a denture, which when manufactured can be placed on at leastone implant placed in a first jaw of a patient, and creating a digitalguide design of a positioning guide configured to maintain properocclusion between the denture and the opposing jaw during placement ofthe denture on the at least one implant, which when manufactured can beused to position the denture on the at least one implant, wherein themanufactured denture is in a desired occlusal contact with a dentalanatomy of a second jaw opposite the first jaw, the method comprising:obtaining a digital first jaw model comprising a surface representationof at least a part of the first jaw and of an at least one expectedimplant site comprising a digital abutment representation of an abutmentarranged at the at least one expected implant site, creating the digitalprosthesis design comprising a distal prosthesis surface and a proximalprosthesis surface, wherein the proximal prosthesis surface comprises atleast one abutment hole and creating a shape of the abutment hole largerthan the digital abutment representation, obtaining a digital second jawmodel of the second jaw comprising a surface representation of at leasta part of the second jaw opposing the at least one expected implantsite, and creating the digital guide design of the positioning guidecomprising a distal guide surface which at least partly comprises ashape corresponding to the shape of a part of the digital second jawmodel and a proximal guide surface which at least partly comprises ashape corresponding to the shape of a part of the distal denturesurface.
 2. The method according to claim 1, wherein creating the shapeof the abutment hole larger than the digital abutment representationcomprises creating the shape of the abutment hole at least partly on anenlarged shape of the digital abutment representation.
 3. The methodaccording to claim 1, wherein the step of obtaining a digital first jawmodel further comprises: obtaining a surface scan of the expectedimplant site, obtaining a radiographic image of the expected implantsite, and arranging the surface scan and the radiographic image in acommon coordinate system.
 4. The method according to claim 1, whereinthe method further comprises that the digital abutment representation isa digital abutment model.
 5. The method according to claim 4, whereinthe method further comprises: selecting the digital abutment model froma digital abutment model library.
 6. The method according to claim 4,wherein the method further comprises: providing a digital implant model,arranging the digital implant model at the expected implant site, andarranging the digital abutment model with the digital implant model. 7.The method according to claim 1, wherein the step of creating thedigital prosthesis design comprises: designing a support structure onthe digital prosthesis design, wherein the support structure is designedto contact at least a part of the surface representation of the firstjaw.
 8. A method according to claim 7, wherein the step of designing thesupport structure comprises: extending the support structure proximallyfrom the digital prosthesis design.
 9. A method according to claim 1,wherein the step of creating the digital prosthesis design comprises:creating a digital gingiva model of the denture, and creating at leastone tooth model of the denture extending distally from the digitalgingiva model.
 10. A method according to claim 1, wherein the step ofcreating the shape of the abutment hole comprises: offsetting thedigital abutment representation outwards.
 11. A method according toclaim 1, wherein the step of creating the shape of the abutment holecomprises: removing undercuts comprising reducing the digital prosthesisdesign, wherein an overlap between the digital prosthesis design and thedigital abutment representation is removed when relatively shifting theprosthesis design and the surface representation of at least a part ofthe first jaw along a desired insertion direction between a positionwhere the digital abutment representation is outside the abutment holeand a position where at least a part of the prosthesis surface and thesurface representation of at least a part of the first jaw align witheach other.
 12. A method according to claim 1, wherein creating adigital prosthesis design of a denture comprises: creating a digitalprosthesis design of the denture, creating a digital guide design of thepositioning guide, manufacturing the denture based on the digitalprosthesis design using a 3D manufacturing process, and manufacturingthe positioning guide based on the digital guide design using a 3Dmanufacturing process.
 13. The method according to claim 12, wherein the3D manufacturing process is 3D printing.
 14. The method according toclaim 12, wherein the 3D manufacturing process is 3D milling.